The M 4 Core Project with HST: I. Overview and first epoch1. Issue 10 (December 2013)

• Record Type: Journal Article
• Authors: Bedin, L.R.; Anderson, J.; Heggie, D.C.; Piotto, G.; Milone, A.P.; Giersz, M.; Nascimbeni, V.; Bellini, A.; Rich, R.M.; van den Berg, M.; Pooley, D.; Brogaard, K.; Ortolani, S.; Malavolta, L.; Ubeda, L.; Marino, A.F.
• Is Part Of: Astronomische Nachrichten. Volume 334:Issue 10(2013)
• Page Start: 1062
• Page End: 1085
• Publication Date: 2013-12
• Subjects: Astronomy -- Periodicals; 520.5
• DOI: 10.1002/asna.201311911
• Languages: English
• ISSNs: 0004-6337

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>We present an overview of the ongoing Hubble Space Telescope large program GO‐12911. The program is focused on the core of M 4, the nearest Galactic globular cluster, and the observations are designed to constrain the number of binaries with massive companions (black holes, neutron stars, or white dwarfs) by measuring the "wobble" of the luminous (mainsequence) companion around the center of mass of the pair, with an astrometric precision of ∼50 µas. The high spatial resolution and stable medium‐band PSFs of WFC3/UVIS will make these measurements possible. In this work we describe (i) the motivation behind this study, (ii) our observing strategy, (iii) the many other investigations enabled by this <italic>unique</italic> data set, and which of those our team is conducting, and (iv) a preliminary reduction of the first‐epoch dataset collected on 2012 October 10. (© 2013 WILEY‐VCH Verlag GmbH &amp; Co. KGaA, Weinheim)</p> </abstract>